Not sure if it is worth buying a video card for system #1 and run pfsense or freenas on it. Will also plan on buying intel NICs for link aggregation. Not sure if this is beneficial for pfsense or a NAS or just use onboard ethernet. Regarding the Ryzen 2700 CPU, is it worth waiting to see if AMD releases a 5 series chipset? Should I put build the 2700 to my main pc, or will it be more beneficial towards pfsense or freenas. Is it possible to run both on one machine? For FreeNAS I plan on buying 4 WD Red drives 6~10 TB (Depends on price) and use it with ZFS. Not sure if ECC Ram is required or not. If ECC Ram is required for ZFS would buying a used server make more sense?

If you're going to use the old machine for pfsense I wouldn't buy a video card just for that. Swipe a card from one of the others and use it just for the initial setup. Once it's up and running there's a web UI you can use to manage things remotely. The only time past that where you'd need a display hooked up to it directly is if something goes seriously wrong and you need direct access to the console. I'd also pull the 320GB drive from the old machine and see if there's a use for it somewhere else. You won't need anywhere near that much storage for a pfsense box.

About link aggregation, I probably wouldn't worry about it. You'd need a managed switch also, and if you're just checking things out then you probably won't care too much about redundancy or having greater than gigabit speeds.

You can run both freenas and pfsense from within virtual machines, but in my opinion it's easier with dedicated hardware. I assume you already have a primary router, and you'd be setting pfsense up as a secondary. In that case it's not so different, but you do need to be aware that all of its clients wouldn't have a connection until the VM comes online.

Do not meddle in the affairs of archers, for they are subtle and you won't hear them coming.

I was thinking it would be easier making pfsense act as a router, and turning my asus rt-n66u into an access point.cable modem -->pfsense box with dual intel nic--> TPLINK 8 Port Switch-->rt-n66U(access point)-->voip adapter (PAP2T-NA), NAS, Printer, and computers. Or is it not recommended for pfsense to be a router? I would also like to run NordVPN through pfsense as well.

But this is the 2nd step, right now my main issue is which system should be running pfsense, and which should be running freenas. Will see if people recommend Virtualization if it isn't too complicated. Will also have to take into account how much power consumption is being used running that 4300 24/7

No that sounds fine to me. The router+AP thing is pretty common. It's how I have things set up here. I just wasn't sure how much you wanted to change your existing setup.

You'll have a chicken/egg problem if you set up pfsense as your primary router from within a virtual machine. The host needs an internet connection also, and it won't be able to get one until your pfsense VM comes online.

If it were me I'd use the E4300 machine for pfsense, and the Processor G620 for HTPC/FreeNAS. The NAS+HTPC combo is also pretty common.

Do not meddle in the affairs of archers, for they are subtle and you won't hear them coming.

Need to buy a Video Card) Has no onboard Graphics . . . Not sure if it is worth buying a video card for system #1 and run pfsense or freenas on it.

If you don't think you'd be using the graphics very often, how about a 2D USB-HDMI graphics adapter? See here.

They're only about $50, so it would be a lot cheaper than a discrete 3D PCIe graphics card. You could either keep the USB-HDMI adapter permanently attached to the computer, or you could just store it in your toolbox for when you need.

If ECC Ram is required for ZFS would buying a used server make more sense?

I'd also consider a cheap system with a Ryzen non-APU. (Cheap relative to a Xeon server.) The non-APU Ryzens support ECC as long as the motherboard does too. For example, most ASRock AM4 motherboards support ECC with the non-APU Ryzens. The Gigabyte X470 Aorus Gaming 7 Wifi also supports ECC, so I use the Gigabyte motherboard with a Ryzen 7 2700X and Kingston DDR4 2666 MHz ECC.

"File systems such as NTFS, EXT4, etc have (data recovery) tools that may allow you to rescue your files when things go bad due to bad memory. ZFS does not have such tools, if the pool is corrupt, all data must be considered lost, there is no option for recovery."

As for memory errors:

"In the best case, bad memory corrupts file data and causes a few garbled files. In the worst case, bad memory mangles in-memory ZFS file system (meta) data structures, which may lead to corruption and thus loss of the entire zpool."

I think it depends on your use-case here, or even IF ZFS is a good idea or not.